741392domain: NAppears in sequencesa(n) = T(2n,n), T given by A026780.at n=9A026781a(n) = T(n, floor(n/2)), T given by A026780.at n=18A026786Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 0), (0, 0, 1), (1, 1, -1)}.at n=14A148281